FORD XR3i : Start up regulator and warm up valve?

Does the engine suddenly appear to run very rich or very weak at the troublesome temperature? There are many things that will cause poor warm up /cutting out not least the warm up reg on this engine.

Disconnect the multiplug on the warmup reg and see what difference it makes. You should find that it runs rich for longer than usual. The warm up reg responds to both heat from the internal heater via the temp sensor under the inlet manifold and from actual engine heat, which is why its where it is. The electrical conenction does the first bit of heating (and thus leans off the mixture) and the heat of the engine does the last bit.

Tim..

Thanks for the suggestion Tim.. Unfortunately it didn't make much difference..

Basically what I did was disconnect the plug located on the top of the warm up regulator then start the car from cold (had been left over night) and let it idle.. About 5 - 7 min the idle starts to become erratic, it splutters a little then the revs pickup a little then it splutters again and the revs pick up again.. This continues and gradually becomes worse and worse until the engine dies..

Then it is very difficult to get it started again (if at all)..

Any other suggestions?

Right.

Swap out the tachometric relay first (above brake pedal, colours blue or pink, about 6 or 7 wires) with a known good one.

This sounds your problem.

(it keeps the fuel pump engaged via a signal from the LT side of the coil, if pulses fall below 300rpm it cuts the pump- they often go wonky)

Tim..

Once the engine is warm it has no problems idling or starting its only during the cold to warm transition.. The reason we were pointed to the warm up regulator is because the car runs fine one its warm..

Would the tachometric relay be the cause of this behavior during warm up or would it always cause there to be an erratic idle (even at normal temp)?

Thanks for your input..

The relays fail in all sorts of states, though it is certainly co-incidence that it causes problems when the engine is warming up. usually a dry joint which opens up as it warms up and causes the problem.

Anyway to be sure its at fault, rig up a bulb to the fuel pump and check its lit brightly all the time the engine is running.

Tim..

I will have a go at it over the weekend.. I really hop that it is the relay.. :)

Thanks.